503RADARINCIDENT ARCHIVEMETHODOLOGY
RESOLVED

Anthropic outage — August 18, 2026

Degraded performance for multiple models

Anthropic’s Claude.ai was disrupted for 3h 01m on August 18, 2026.

Key facts

DetectedAugust 18, 2026 · 16:23 UTC
Confirmed16:23 UTC
Resolved19:24 UTC
Duration3h 01m
ServiceClaude.ai

Timeline

  1. 16:23Z

    Detected · Official

    Reported directly on ANTHROPIC's official status page — no earlier independent (crowd / dependency / measurement) signal.
  2. 19:24Z

    Resolved

    Signal volume fell back below the threshold; the event was closed.

How this was detected

1 independent evidence class for claude-ai on ANTHROPIC. 2 crowd reports across bluesky (single platform — not corroborating), z=+0.1σ vs the cell baseline. Official notice confirms it.